Buzz Blog

Citizen Science: Testing the Fairness of US State Quarters

Friday, August 02, 2013

As we were sitting around gambling our lunch money away today (note: we don't endorse gambling or take part in it during work hours), one of us happened to wonder whether one coin or another might be better for pitching pennies (note: see previous note about how we don't gamble at work).

The three possible results of flipping a quarter: tails, edge, heads.
That naturally led to the question of whether the many different designs of new US quarters might affect the balance or aerodynamics of a flipped coin in ways that would make them more likely to land on one side than the other.

You would probably expect that if you flip a quarter many times it should land heads up just about as often as it lands tails up. In that case, the coin would be considered "fair." But if one or more of the newly issued quarters isn't fair, it could have implications for all sorts of things from letting a coin flip make major life decisions for you, to determining whether you're favorite Pop Warner football team will be better able to beat the spread (note: see above notes) if they happen know a quarter from Nevada, just to randomly pick a state, will more frequently come up heads during the opening coin toss.

What better way to scientifically test the fairness of  commemorative US state quarters than enlisting the millions of Physics Buzz readers in a grassroots experiment? So help us out by flipping some quarters and reporting the results in our survey form below.



You may have noticed that we included a nod to a quarter's third stable orientation on a flat surface - in addition to ending heads up or tails up, it can potentially wind up standing on edge. Although the local potential minimum is much shallower, it's still entirely possible. We don't expect many quarters to stand on edge, of course.

In case you're interested in sharing this experiment with one of your friends who may also own a quarter, you can send them this link to the survey. We'd appreciate the help. The more flips we get, the better our stats and conclusions.
Posted by Buzz Skyline


Anonymous said...

Im doing this for a school project and i need the results in order to complete my project. Where could i go to find them or who should i talk to

Friday, May 12, 2017 at 11:29 AM

Anonymous said...

Where's the results?

Wednesday, October 19, 2016 at 11:24 PM

Anonymous said...

Since I've learned how to manipulate the outcome of coin flips, I constructed a coin flipping device out of lego to eliminate any human variables. Loads of data incoming!

Wednesday, October 30, 2013 at 12:43 AM

Anonymous said...

My students are flipping coins and adding data for you. Is there anytime soon that we might see the results?

Friday, October 11, 2013 at 12:04 PM

Anonymous said...

Really interesting, thanks!

I think that you would be really interested in some recent research that I have come across about crowds and citizen science.

It’s called “The Theory of Crowd Capital” and you can download it here if you’re interested:

Really powerful stuff!

Saturday, August 3, 2013 at 7:20 PM